GPRS doc

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Company Confidential

1 2005 Nokia V1-Filename.ppt / yyyy-mm-dd / Initials

(E)GPRS Network Infrastructure

GPRS IPBackboneNetwork

DNS

CG

GGSN

Internet

Corporate 1Intranet

LIG

Corporate 2Intranet

SS7Network

PSTNMSCBSCBTS

MS

EIR

HLR/AuC

SMS-GMSC

SGSN

SGSN

SGSN

MODEMPOOL FOR DIALUP

Nokia IP650sec GW

Router

Router

RouterSTM-1

STM-1

SGSN

GGSN

Router

Router

NokiaSecurity GW

LANSWITCH

MODEMPOOL FOR DIALUP

NokiaSecurity GW

NokiaSecurity GW

Nokia IP650sec GW

Nokia IP650sec GW

NokiaSecurity GW

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BSC

Metro

Hub

SGSN

GGSN

ELECTRICAL ET

GB LINKGB LINK

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NSEI 1 NSEI 2

NSEI 3

NSEI 4

NSEI PLANNING

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Network Element and Configuration Audit - Summary

BSCGGSN

IP/MPLS/IPoATM-

Applicatio

n Servers(co-

located

2GSGSN

BTS

HLR/AC/

EIR

TCSM

TC

MSC/VLR

Abis GbBSC

BSCGGSNGGSN

-backbone

ApplicationServers

2G

SGSN

2G

SGSNBTS

HLR/AC/

EIR

HLR/AC/

EIR

TCSM

TC

MSC/VLR

GnGi

Gs

RF interface

Coverage

C/I

Capacity

Traffic volume

Mobility

MS/Clientparameters

GPRS/EDGEcapability andrelease

Multislot support

Abis interface

EDAP size /dimensioning

# of E1/T1s

GPRS/EDGEtraffic

Gb interface

Bearer size IP v.s. FR

Dimensioning

BTS

GPRS territory

BTS HWconsiderations(TRX & BB-card)

BTS SW(EPCR)

BSS

PCU variant &dimensioning

PCU strategyin mixedconfiguration

BSS SW andfeatures

SGSN

Unit capacity(PAPU etc.)

BSS Gb Flowcontrol

RF

Server

load

settings(Linux/Win)

HLR

QoS profile

GPRS settings

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INPUT GIVEN FOR THE GPRS PLANNING

No. of time slot required for the GPRS territory : CDED=1 and CDEF=1

No. of BTS per EDAP i.e the No. of sectors prevalent : 3 No. of time slot used for EDAP on Abis (64 Kbps) : 3 Time slot

% of upgrade is the Teritory upgrade for the future perspective : 10 %

No. Of sites planned per BSC : 100

Access rate (CIR) is the speed required at the GB interface : 256 Kbps

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OUTPUT REQUIRED

No. of sites per NSEI required

No. of NSEI required in BSC No. of PCU or No. Of BCSU required

No. Of Gb Link required

No. of E1 required from the BSC to Metro Hub

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How to calculate what

No. of EGPRS resources used in 1 sector * No. of sectors : 2 x 3

No. of time slot/sector * no of time slot used for EDAP :- 2 * 3 = 6 So total time slots per site 6 + 6 = 12

1 NSEI support 256 time slot with upgrade % as 10 so total no of time slots which

can be equipped is 256 - 10% of 256 = 230.4 ~ 230

So no. of sites per NSEI is 230/12 = 19.16 ~ 19

So no NSEI required / BSC : 100 / 19 = 5.2 +1 (for future use) ~ 6

2 NSEI supports 1 BCSU so no. of PCU required : 6/2 = 3

No. of NSEI required is equivalent to the no. of Gb link = 3

On 1 E1 we can get 31x64 = 1984 , so access rate can be given by 1 E1 = 1984/

access rate (256) = 1984 / 256 ~ 7

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Coding scheme Data rate

MCS-1 8.8 kbit/s

MCS-2 11.2 kbit/s

MCS-3 14.8 kbit/s

MCS-4 17.6 kbit/s

MCS-5 22.4 kbit/s

MCS-6 29.6 kbit/s

MCS-7 44.8 kbit/s

MCS-8 54.4 kbit/s

MCS-9 59.2 kbit/s

Abis PCM allocation (fixed + pool)

ransm ss on requ remen orEGPRS coding schemes in Abisinterface

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EDGE modulations

Scheme Modulatio

n

Maximum rate [kb/s]

MCS-9 59.2

MCS-8 54.4

MCS-7 44.8

MCS-6 29.6 / 27.2

MCS-5

8PSK

22.4

MCS-4 17.6

MCS-3 14.8 / 13.6

MCS-2 11.2MCS-1

GMSK

8.8

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GPRS & EGPRS coding schemes

GPRS has four coding schemes,

CS-1...4. All use GMSK.

EDGE has nine modulation and coding schemes, MCS-1...9.

MCS-1...4 use GMSK,

MCS-5...9 use 8-PSK modulation

Operator can set the MCS to start with

E.g. always start with MCS-9

MCS-7

MCS-1

22

MCS-228

MCS-3

37

MCS-4

44

MCS-5

56

MCS-6

74

5656

MCS-8

6868

MCS-9

74 74

redundancy from

channel coding

RLC data block,number of octets

RLC/MAC block

(radio block)

CS-1

20

CS-2

30

CS-3

36

CS-4

50

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EDGE link performance

GPRS with re-transmission with same coding scheme

Retransmissions with EDGE can be sent with the new scheme

Bit Error Probability (BEP) is a new MS quality measurement introduced

In general, a higher coding scheme has higher coding rate, and consequently higherpeak throughput, but it also tolerates less noise or interference.

New parameters

Max BLER for Ack and Non-Ack modes

Can be used to tune to use more higher MCSs

Mean BEP offset for GMSK and 8-PSK

Set threshold for MCS change

The figure shows throughput vs. C/I of EGPRS coding schemes in TU50iFH, without

incremental redundancy.

0

10

20

30

40

50

60

0 5 10 15 20 25 30

MCS-1

MCS-2

MCS-3

MCS-4

MCS-5

MCS-6

MCS-7

MCS-8

MCS-9

Ideal Link AdaptatiIn RLC layer (kbit/TSL)

C/I

)
http://nea.ntc.nokia.com/~neva/PMWG_2GBSS/GPRS_territory.htm

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GPRS: territory (S9-10)

AVG. AVAILABLE TCH in CS territoryava_15 (S9)ave_avail_TCH_sum/ ave_avail_TCH_den

AVG. AVAILABLE GPRS CHANNELS in PS territoryava_16 (S9)ave_GPRS_channels_sum/ave_GPRS_channels_den

AVG. AVAILABLE DEDICATED GPRS CHANNELSava_17 (S9)ave_GPRS_channels_sum/ave_GPRS_channels_den

PEAK DEDICATED GPRS CHANNELS

/c2066(S9)peak_permanent_gprs_ch

PEAK GPRS CHANNELS

/c2063(S9)peak_gprs_channels

Used capacity for GPRS

The following are the operator configurable parameters for territory

management:

GPRSenabled (BTS-level)

GPRSenabledTRX (TRX-level)

DedicatedGPRScapacity (BTS-level)

DefaultGPRScapacity (BTS-level)

PreferBCCHfreqGPRS (BTS-level)

TerritoryUpdateGuardTimeGPRS (BSC-level)

GENA

GTRX

CDED

CDEF

BFG

GTUGT

ADDIT.GPRSCH USED

ach_1

UNAVAILABLE

TCH

c2040

AVG. BUSY TCH = CS traffictrf_12bave_busy_tch/ res_av_denom14

AVG. TSL used for UL GPRS trf_78b

AVG. TSL used for DL GPRS trf_79b

Free capacity

Allocated resources

Usedresources

CDEDCDEF

Used capacity for speech

Availability ava_1d

The main principle is thatGPRS (PS) uses the capacity

that remains from the CStraffic.

Given as % over dual TCH tsls of

GPRS enabled TRXs.

Includes dedicated time slots.

Rounded downwards.

Circuit Switched traffic has priority

In each cell Circuit Switched & Packet Switched territories are defined

Territories consist of consecutive timeslots

TRX 1

TRX 2

CCCH TS TS TS TS TS TS TS

TS TS TS TS TS TS TSTS

DedicatedGPRS

Capacity

CircuitSwitchedTerritory

PacketSwitchedTerritory

Territory border movesDyn a m ica lly based onCircuit Switched traffic load

CircuitSwitchedcapacitynotaffected

byintroducingGPRS

DefaultGPRS

Capacity

AdditionalGPRS

Capacity

DL D t S h d li E l N d t
http://nea.ntc.nokia.com/~neva/PMWG_2GBSS/GPRS_territory.htmhttp://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?ava_15http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?ava_15http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?ava_16http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?ava_16http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?ava_17http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/counters?002066http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/counters?002063http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?ava_15http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?ava_15http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?ava_16http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/params?942http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/params?962http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/params?940http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/params?941http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/params?943http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/params?949http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?ach_1http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/counters?2040http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?trf_12bhttp://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?ava_15http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?trf_78bhttp://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?trf_79bhttp://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/params?940http://essrv509ntc.ntc.nokia.com:6336/dynaweb/NED31_bsc_s9e/0031312/@ebt-link;nh=1;pt=46768;uf=0?root=%25N%15_46776_START_RESTART_N%25;stylesheet=table.rev;window=new;title=%22Table+124%3A+%22;__prev_hit__=46773;DwebQuery=CDEFhttp://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?ava_1dhttp://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?trf_12bhttp://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?ava_15http://essrv509ntc.ntc.nokia.com:6336/dynaweb/NED31_bsc_s9e/0031312/@ebt-link;nh=1;pt=46768;uf=0?root=%25N%15_46776_START_RESTART_N%25;stylesheet=table.rev;window=new;title=%22Table+124%3A+%22;__prev_hit__=46773;DwebQuery=CDEFhttp://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/params?940http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?ava_17http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?ava_1dhttp://essrv509ntc.ntc.nokia.com:6336/dynaweb/NED31_bsc_s9e/0031312/@ebt-link;nh=1;pt=46768;uf=0?root=%25N%15_46776_START_RESTART_N%25;stylesheet=table.rev;window=new;title=%22Table+124%3A+%22;__prev_hit__=46773;DwebQuery=CDEFhttp://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/params?940http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?trf_79bhttp://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?trf_78bhttp://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?ava_15http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?trf_12bhttp://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/counters?2040http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?ach_1http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/params?949http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/params?943http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/params?941http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/params?940http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/params?962http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/params?942http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/counters?002063http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/counters?002066http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?ava_17http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?ava_16http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?ava_16http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?ava_15http://nea.ntc.nokia.com/cgi-bin/cgiwrap/neva/frmls?ava_15http://nea.ntc.nokia.com/~neva/PMWG_2GBSS/GPRS_territory.htm

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RTSL

RequestsTRX 10 1 2 3 4 5 6 7

- - CS-2 MCS-1 MCS-9 MCS-7 MCS-1 MCS-7

Grants- - CS-2 MCS-1 MCS-9 MCS-7 MCS-1 MCS-7

PCMT

SL

PCM subTSL1 2 3 4

8

11

10

9

5

2

5

-

5

-

-

-

7 7 7 -

4 4 4 4

There are enough EDAP resources to handle adequately all the TBFs andMCS requests. (e.g PS Active EGPRS ch < EDAP resources)

DL Data Scheduling ExampleNo need toshare case

DL D t S h d li E l ( h i )

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DL Data Scheduling Example (sharing case)

Grants

RTSL

RequestsTRX 10 1 2 3 4 5 6 7

- - CS-2 MCS-5 MCS-9 MCS-8 MCS-1 MCS-7

- - CS-2 MCS-5 MCS-7 MCS-7 MCS-1 MCS-6PCU-TRX 0

5

2

35

7

5

7

44 4 -PCMT

SL

PCM subTSL

1 2 3 4

11

12

10

-

Because EDAP is a shared resource between a higher number of EGPRSTSL it is possible to encounter the situation where there are not enough EDAP

resources to handle adequately all the TBFs (e.g PS Active EGPRS ch >EDAP resources)

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EDAP utilization

TRX 2

TRX 1

TS TS TS TS TS TS

TS TS T TS TSTS TS TSSPBCCHBCCH

TSTS

TS

TS

Dedicated EGPRS TSL

Default territoryEGPRS TSL

6 EGPRS RTSLs (Dedicated + Default territory)

50 % utilization assumed (3 Data Erlangs traffic) On average 3 RTSLs used

RTSLs use MCS7 (44.8 kbit/s) with average C/I=13dB and throughput30kbit/s

Effective data rate factor excluding retransmissions over the air-interfaceis 30/44.8 ~ 0.7

Slave group utilization is 0.7*0.5= 0.35

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PLAN A PLAN B

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SNO PLAN A PLAN B

1

Both Non BCCH and

BCCH Trx can access the

EDGE Facility

Only BCCH TRX can access the

EDGE facility

2

If the BCCH TRX goes

faulty then also the EDGE

users can access the N/W

since the 2nd TRX has

been defined on the

EDAP Pool

If BCCH TRX goes faulty then The

EDGE Service can not be accessed

since the 2nd TRX has not been

defined on the EDAP POOL

3

Using this plan we canchange the BFG priority

depending on the

Interference in the N/W

We can not change the BFG unstill and

unless the EDAP pool need to be

redesigned

4

In case of extending the

time slot of EDGE in Non

BCCH TRX also can be

done if congestions is

observed in the Site

We can not extend the Non BCCH

TRX time slot during the congestion

since that TRX is not mapped on the

EDAP Pool

5

While expanding the N/W

from the 222 to 332

configuration we need to

Modify the EDAP pool

Need not to modify the EDAP pool

since only BCCH TRX is being mapped

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Conclusion

The No. of sites per NSEI depend on the EDAP pool size and no. of time slot

used for the GPRS territory

Beside if we need to extend the resourced at ABIS end we need to defince the

EDAP pool

If we require the Speed at GB we need to go to higher CIR

Documents

GPRS doc